The Statistics and Data Management Core's principal aims are to provide cross-component data management and to assure that data analysis both within components and across the entire Center are conceived and executed utilizing theoretically sound assumptions and optimal statistical methodologies. This Core also aims to advance biostatistical science by developing, as appropriate, novel or enhanced approaches to modeling predictions based on longitudinal information that involves changing influences of covariates over time. The two key areas of activity of the Core are: Data Management; To assist Cores and projects in gathering and organizing data to ensure cleanliness and consistency; To train and assist the HNRC personnel in the use of the computer equipment, software and databases which are necessary to athe efficient operation of the Center; To validate, enter and update selected data into a commonly shared Central Database; To facilitate access by Cores and Projects to data and subject information; To provide timely and accurate aggregate information on subjects and variables of interest; To trouble-shoot and maintain the HNRC computer hardware, network, software, and licenses; To review and recommend computer equipment purchases and software upgrades; To provide feedback to Cores and projects on data errors or inconsistencies found when importing; To assure the confidentiality and physical security of the data gathered; Statistics: To consult with the various Cores and Projects on project design and data analysis plans and needs in order to standardize methods and ensure viability; To consult with other investigators on issues concerning statistical modeling; To reduce Core data to composite variables of interest, in preparation for specific analysis; To conduct advanced analyses of study data including longitudinal, logistic, and survival analyses, with particular emphasis on cross-core and cross-project analyses; To explore new statistical methods of analysis while in the process of answering the real-life questions that are hypothesized.